This week, we've an unusual treat, a contemporary poem by a writer who works in the language of the Troubadours, Occitan. "Lo temps s'es perdut …"/ "Time has disappeared …" by Aurélia Lassaque, appears in her new collection, Solstice and Other Poems, a bilingual volume with Lassaque's Occitan originals and English translations by James Thomas elegantly set out on facing pages.

Although I'm told its closest relative is Catalan, if you have a smattering of any Romance language, you'll be on the way to understanding Occitan. It's a language many readers will have met before. In The Divine Comedy, Dante gives the troubadour Arnaut Daniel, who appears in the Purgatorio, a speech in Occitan. A bit nearer our own time, there are Occitan passages in Kate Mosse's 2005 novel, Labyrinth. The name comes from "Lenga d'òc" ("the Òc language"), "òc" being the word for "yes." It's spoken in the Southern part of France, in Monaco, and in smaller areas of Spain and Italy – regions sometimes collectively known as Occitania. In France, native Occitan speakers are mostly also native French speakers, and Lassaque composes in both languages.

The "Solstice" collection of poems and poem-sequences is impressionistic and sensuous, glowing like "a beaker full of the warm South". Earth and fire are the dominant elements. The poem I've picked has an airy quality, as well. It captures a moment of feeling and imagining so intense that boundaries between images, like the consciousness of time, have been erased or fractured.

In English, the concept of lost time can suggest both what has passed and what has never been experienced. It could imply missed opportunity, or time wasted. "Time flies," as we say. Here, the main impression is that time has simply ceased to exist.

Some images imply dismemberment. It's only the young girl's face which "takes flight" and this is compared to a "bird without a body" – as if even the face might simply be a voice, disappearing, like time, "into the air-tracks". The poem goes on to suggest that a potent physical experience began the trajectory, even though it was "oblivion" that gave the protagonist "a morsel of moonless night/ Left on her lips". The alliteration in the English translation heightens our sense of the tactile.

Those "air-tracks" could, of course, evoke literal flight: an aircraft's flight-path or the vapour-trails it leaves. Flight, like disappearance, is a significant theme, and the poem is haunted by the myth of Icarus – not by accident one of modern poetry's favourite parables.

The central event in this complicated legend concerns Icarus and his father Daedalus, a brilliant artificer. Both were imprisoned by King Minos, but escaped the tower where they were held captive, using wings devised by Daedalus from birds' feathers and wax. Icarus, thrilled by his ability to fly and forgetting his father's warning, soared towards the sun: the heat melted the wax, the wings disintegrated, and the boy plunged to his death in the sea. Earlier in the story, Daedalus has tried to kill his rival, a gifted young apprentice, by pushing him from the Acropolis. Athena has saved this boy, sometimes named Perdix, by transforming him into a bird.

The allusion to the "Icaria sky" suggests both the myth and its setting. The poem's flight-path, however, is an ascent rather than a fall. I imagine "Icaria sky" as vivid blue, and the "black pearl" of the girl's tear expanding surreally to bring night and perhaps death. Perhaps a female Icarus has also soared too near the sun, but the hubris has condemned her to eternal flight.

The lines beginning "She'll never touch earth …" are incantatory, like a lament. The girl has sacrificed a close, playful relationship with nature ("She'll never tease the stone/ nor the trees…"). Or perhaps she has never belonged to earth at all: "she married an illusion" instead. Was it the illusion of flight or the illusion of love, was it self-deception or the deliberate choice of airy other-worldliness?

The Icarus myth may crudely be interpreted to mean that human skill is fallible and punishable. But that seems too heavily literal for this poem. The dissolution is widespread. It's not only that of time and the girl: the trees, too, seem lost in the wrong element, in "the waters that confound them".

The contrast of weight and weightlessness is nicely conveyed in images that sometimes evoke evanescence ("air-tracks") and sometimes fragile solidity ("black pearl", "morsel"). The English language adds more physical weight and hard sound, with the audibility of the relative pronoun, "that", and the predominance of masculine line-endings contributory factors. The texture of the Occitan poem seems more light and rippling, so that weightlessness is predominant, and the melancholy mood enhanced by the falling cadences.

"Lo temps s'es perdut …" is one of the untitled poems in the book's final section, :"Alba dels Lops: Divèrses Poèmas" ("Dawn of Wolves: Various Poems"). James Thomas's translation is followed, in the closest we can get to facing pages, by the Occitan original in italics.

Time has disappearedInto the air-tracksWhere a young girl's face,Bird without body,Takes flight.From her eyes a black pearlEscapes to Icaria sky.She's daughter to oblivionThat bequeathed herA morsel of moonless night,Left on her lips.She'll never touch earthShe'll never tease the stoneNor the treesNor the waters that confound them.She married an illusionThat vanished in the wind.